In simple control products where a relay simply must be closed and opened and possibly have a time-out or other additional simple functions, there are many circuit configurations that can be used. Generally, each configuration includes a power supply, the relay, the control switch, a logic section to coordinate the switch with any time-out or other function, and a driver for the relay. For cost effective manufacturing, each of these functional areas over the years have been reworked many times to reduce the number of components for each section but generally speaking all of these functional sections can be identified independently in most design configurations.
Component count and cost may be further reduced by eliminating entire functional sections or combining them. Both of these approaches have been used in the current invention.